Lubricating oil compositions, inhibitors therefor, and methods of manufacturing the same



I by straight mineral oils.

Patented May 9, 1%39 ZJSYAW LUBRICATIN G OIL COM'POSITIONS, ITORS THEREFOR, AND

ammo

MANUFACTURING THE seam Troy Lee Cantrell and John Gordon Peters, Lansdowne, Pa., assignors to Gulf Oil Corporation, Pittsburgh, Pa, a corporation of Pennsylvania No Drawing. Application September 17, 1936, Serial No. 101,339

8 Claims.

Our invention relates to lubricating oils and more particularly to lubricating oil compositions containing an oil-soluble agent or agents effective to inhibit or mitigate the normal corrosive or destructive action of lubricating oil deterioration products upon certain types of bearing metals under certain conditions of use, said agent or agents also having the properties of imparting so-called extreme-pressure characteristics to the lubricating oil compositions, and also being effective to reduce or eliminate undesirable oxidation changes in the oil.

Despite the many technological advances made in the art of refining and applying lubricating oils and in the composition of bearing materials, modern lubricating oils and bearings often fail to perform satisfactorily. It is well known in the art that straight petroleum lubricants have fairly well defined limits of bearing speeds, pressures, and temperatures within which they will give acceptable service. These limitations are often exceeded in modern designs, resulting in machines that cannot be satisfactorily lubricated These modern designs are justified by engineers in their efforts to provide machines to conform to the ever-increasing demand for compactness, speed, power and acceleration in modern engines. Many modern designs have already exceeded the above-mentioned limits wherein straight petroleum lubricating oils perform acceptably; therefore, it is necessary to provide lubricating compositions that extend and widen the limits formerly associated with straight lubricating oils.

Moreover, highly parafiinic oils having excellent viscosity-gravity constants, volatilities, carbon residue values, and resistance to sludging and oxidation, and hence of high value for use under relatively mild lubricating conditions, sometimes tend to be even less satisfactory than the less highly parafiinic oils, when the ordinary limits of temperature, pressure, and bearing speed are exceeded. This may be due in part'to the fact that the deterioration products of paraffinic constituents are more active than those resulting from naphthenic or other nonparafl'inic constituents, and it may be due also to the fact that the nonparaffinic constituents have some inhibiting effect upon either the deterioration of the paraf linic constituents or upon the behavior of products resulting from such deterioration, at high temperatures and pressures and in the presence of certain metals. However, the inhibiting value of the nonparafiinic constituents is low per unit concentration, and they are less satisfactory with respect to viscosity-gravity constant, carbon residue, and similar criteria of lubricating quality than the paraflinic constituents. A more satisfactory solution of the problem would be to substitute for the nonparaflinic constituents removed in the more drastic refining treatments or absent because of the highly paramnic nature of the original stock, some inhibiting or mitigating agent which would be far more effective per unit concentration and hence less detrimental with respect to the other physical properties which also affect the ultimate lubricating value of the oil.

Improved bearing metals have recently been developed which are mechanically advantageous under many operating conditions. These bearing metals include binary and ternary alloys of cadmium, silver, copper, lead, and nickel; as examples of such improved bearing metals frequently employed at the present time we may mention cadmium-silver, cadmium-silver-copper, cadium-nickel-copper, and copper-lead alloys. However, such alloys are more subject to chemical attack than babbitt and other bearing alloys used in the past, and their use at high temperatures, high speeds, and high pressures is sometimes accompanied by a deterioration of the oils employed for their lubrication, which in turn may destroy the bearings. The exact mechanism of this action is no doubt complicated and is perhaps not fully understood; it is quite possible that some of the metals present in the bearings tend to promote such deterioration, and that other metals present are subject to attack from the deterioration products. Whatever the cause or the mechanism, the result is that the combination of drastic lubricating conditions and alloy bearings of the general nature indicated frequently causes trouble; the bearings may be badly etched or corroded, and the quality of the oil may be rapidly deteriorated.

It has been observed in some cases that the more highly paraflinic oils are apt to cause more difliculty in this respect than less paraffinic oils. It is highly desirable, therefore, to provide means whereby the oils may be so improved as to give satisfactory operating results under the conditions noted, and this is especially true insofar as concerns the more highly paraflinic oils, which should and do command a premium in price.

Moreover, it is well known that all hydrocarbon oils are more or less subject to changes through oxidation, resulting in undesirable deterioration, acid formation, and increase in carbon residue, viscosity, sludging, and the like. Such oxidative changes may become more rapid or more far-reaching in extent in the presence of metals such as those employed in modern bearings for example those of the general class mentioned above.

In order to meet these problems and to provide more satisfactory lubrication under the conditions indicated, various improvement agents have been incorporated in hydrocarbon oils prior to their sale and use.v Some of these are extremely effective but too expensive for general use. Others, while having satisfactory inhibiting or mitigating characteristics, are unsatisfactory for other reasons. A primary requisite of any such improvement agent is good oil-solubility under service and marketing conditions; moreover, since solubilities vary in different types of oils, the improvement agent should be capable of being added in the requisite amount to oils of different characters.

The improvement agent should also be highly effective per unit concentration in the lubricating oil compositions; otherwise it would be necessary to add such an amount of the improvement agent as to substantially modify many of the desirable physical properties of the lubricating oil itself. The lubricating oils in which the improvement agents are incorporated have been carefully refined to *meet exacting specifications, and if it is necessary to incorporate therein a relatively large amount of some agent differing in physical properties from the oil itself, the resulting composition may prove unsatisfactory for the very purposes for which the lubricating oil was prepared. In general, it is desirable that the improvement agent should be effective at concentrations not exceeding one or two per cent by weight of the lubricating oil, although somewhat higher concentrations may occasionally be justified for special purposes.

It is therefore an object of our invention to provide an improvement agent or inhibitor for addition to hydrocarbon lubricating oils, having a satisfactorily high degree of solubility in hydrocarbon oils, even the more highly refined or more highly paraflinic oils, having a substantial inhibiting or mitigating effect upon the destructive action of lubricating oils upon alloy bearing surfaces under actual conditions of use, where such destructive action would otherwise take place, and which when added to hydrocarbon oils will not result in sludging or forming deposits at ordinary or moderately elevated temperatures upon metallic packaging materials such as tin plate, terne plate and the like, or other common metal surfaces.

It is also an object of our invention to provide an improvement agent or agents of the character indicated herein having the property of imparting desirable extreme-pressure characteristics to hydrocarbon oils when incorporated therein.

Another object of our invention comprises the provision of an improvement agent or agents for addition to hydrocarbon oils, having desirable anti-oxidant and stabilizing properties, and

effective to retard increases 'in viscosity, carbon residue, acidity, and 'sludging of both highly paramnic and less highly parafflnic oils.

A further object of our invention is to provide improved lubricating compositions comprising hydrocarbon lubricating oils having certain improvement agents incorporated therein.

' per cent. Various A still further object of our-invention is to provide a method or methods of manufacturing improvement agents having desirable characteristics for addition to mineral oils.

Our invention has for further objects such additional operative advantages and improvements as may hereinafter be found to obtain.

In the co-pending application of Troy Lee Cantrell and James Otho Turner, Serial No. 99,662, filed September 5, 1936, there is disclosed the preparation of inhibitors of the general character indicated by reacting phosphorus trichloride with certain anti-oxidants, said antioxidants comprlsing water-insoluble reaction products obtained by reacting phenols with olefins.

' We have now found that exceptionally advantageous inhibitors may be prepared by reacting upon the inhibitors disclosed. in the aforesaid co-pending application with anhydrous ammonia or certain amines. Assuming the product's obtained in accordance with the aforesaid co-pending application to be phosphite esters of certain types of alkylated phenols, the products formed in accordance with our present invention may be described as ammonium salts or amino-derivatives of such esters, although we do not desire to limit our invention to any particular theory, nor is it necessary to positively identify or classify any of the compounds prepared in accordance therewith.

Anti-oxidants of thegeneral class indicated and methods of preparing the same are disclosed in the prior co-pending application of Stevens and Gruse, Serial No. 702,258, filed December 13, 1933, and the oo-pending applications of Troy L. Cantrell, Serial No. 64,413, filed February 1'7, 1936, and Serial No. 99,488 filed September 4,

1936, to which reference may be had for further details. The disclosures of the co-pending ap plications referred to hereinbefore constitute in effect a part of the disclosure of the present application insofar as relates to the preparation of such anti-oxidant materials and reaction products obtained by treating such anti-oxidant materials with phosphorus trichloride.

Referring, for example, to the aforesaid application, Serial No. 99,488, there is disclosed a process of manufacturing anti-oxidants wherein a phenol is mixed with from 1 to per cent sulfuric acidhaving a strength of from 60 to 100 per cent, or even fuming sulfuric acid, and an olefin or a mixture of. olefins is passed, preferably in the vaporous or gaseous phase, through the liquid mixture until the phenol undergoing reaction has gained in weight from 100 to 200 per cent or thereabouts, followed by washing the products so obtained with water and caustic soda solution, the concentration of which does not exceed phenols may be employed; for example, phenol (CsHsOI-I) itself, the three cresols (C6H4-CH3OH) and certain xylenols (C6H3-(CH3)2OH), or crude cresylic acids may also be employed. The phenolic starting material should be as free as possible from pyridine bases; such pyridine bases may be removed by conventional methods such as washing with acid or by distillation. As olefinic material there may be employed individual olefins themselves, mixtures of olefins, or mixtures of olefinic and non-olefinic materials. By way of .example, the olefinic material may be butylenes, amylenes, refinery gases containing normally gaseous olefins (ethylene, propylene, butylene) in varying amount and cracked distillates or other relatively low-boiling hydrocarbon mixtures containing normally liquid olefins, and in some in stances also containing substantial amounts of dissolved normally gaseous olefins.

Where the reaction is conducted with the olefin in the gaseous phase, the product is relatively highly concentrated with respect to effective anti-oxidant material and may not require distillation or concentration for the purpose of isolating the latter. On the other hand, when the reaction is conducted with the olefinic material in liquid phase, and especially where the concentration of olefins in the starting material is comparatively low the anti-oxidant-phenol-olefin reaction product may be relatively dilute, comprising, for example, a solution of such anti-oxidant in gasoline-like polymers or unreacted liquid hydrocarbons. In such case the anti-oxidant material may be, and preferably is, concentrated by distillation or otherwise as set forth in the above mentioned co-pending applications, prior to use in the process described herein.

The exact chemical and structural nature of the anti-oxidant materials as thus prepared and employed as a starting material in the manufacture of our improved addition reagents is largely obscure. Although we have been able to identify certain types of compounds in these anti-oxidant materials, it will be realized that especially since mixtures of various phenols and mixtures of various olefins are frequently employed in the manufacture of these anti-oxidants, the number of possible chemical compounds is large and varied. In general they differ from the simple alkylated phenols in that they are insoluble in dilute caustic soda solution and in that they are good anti-oxidants and gum-inhibitors, whereas simple alkylated phenols are not. In general, also, the alkylations in such instances as they occur areof secondary and tertiary types; the methods set forth in the above co-pending applications do not produce normal or primary alkylation linkages. Alkylated phenols with normal or primary linkages are undesirable (except as regards cresols and the like, used as phenolic raw material for the preparation of the anti-oxidants), due to the fact that both such materials and their products of reaction with phosphorus trichloride tend to be relatively insoluble in high gravity lubricating oils. It is possible that certain alkylated phenols of normal or primary linkage might be satisfactory as anti-oxidant starting materials provided the chains were long enough, say chains of 4 carbon atoms or more, on account of the closer resemblance in structure of such compounds to paraflinic lubricating oil constituents. However, this is doubtful, and such compounds would be expected to be of prohibitive cost.

We have identified as constituents in the various anti-oxidant materials prepared as set forth hereinbefore such compounds as follows:

Ortho-isopropyl phenol Ortho-tertiary butyl phenol 2,4-di-tertiary butyl phenol Ortho-isoamyl phenol Ortho-tertiary-amyl phenol In addition to the above listed compounds, similar derivatives of various homologues of mono-, di-, and poly-hydroxy-phenols may be present. It may be remarked, however,'that while some constituents of such anti-oxidants may be identified, it is dimcult or impossible to identify all of the constituents of any one anti-oxidant material of the character indicated, and it is equally impossible to say which particular compound or type of compound may be of most importance. As a matter of fact, we have not been able to isolate or identify any single constituent nor to recover any fraction of the concentrated antioxidants prepared in accordance with the aforesaid Cantrell application Serial No. 99,488, which constituent or fraction has an anti-oxidant value as high as that of the total concentrated product. Nor for the purposes of our present invention is it necessary so to do; the fact remains that antioxidants may be prepared in the manner set forth herein and in the aforesaid co-pending applications, and such materials comprise suitable starting materials for the manufacture of phosphoruscontaining improvement agents or inhibitors in accordance with our present invention. Certain of the constituents of the anti-oxidant starting materials which are not in themselves effective as anti-oxidants are nevertheless capable of being converted by reaction with phosphorus trichloride and subsequent reaction with anhydrous ammonia or an amine to yield phosphorus-containing materials useful as inhibitors.

We prefer to employ as initial starting material anti-oxidants prepared as set forth above and in the aforesaid co-pending applications and having physical prope ties within the following ranges:

Gravity A. P. I Specific gravity: 60/60 F Viscosity, S. U. V. at F.: Sec.

15.0 to 25.0 0.9659 to .09042 150 to (solid) Our invention in its broadest aspects, however, is not limited to the preferred initial starting material mentioned hereinabove, but contemplates the manufacture of inhibitors of the general class described from any alkylated phenols so long as such alkylated phenols possess anti-oxidant properties, are insoluble in water, insoluble or only slightly soluble in dilute alkali, and are permanently soluble up to 5 per cent in paraflin oils. It is a requisite of such alkylated phenols, however, insofar as the present process is concerned, that the compounds shall contain one or more secondary or tertiary carbon linkages or both.

The anti-oxidant value of this initial starting material should be such that the addition of 0.01 per cent by weight thereof to standard gasoline stock having an oxygen stability period (E. G. 0. Method) of say minutes will raise the oxygen stability to at least 240 minutes. Less potent anti-oxidants are unsuitable as starting materials.

The character of the final phosphorus-containing inhibitor will of course vary with the character of the phenolic and olefinic material employed in the manufacture of the anti-oxidant starting material, with the extent of the absorption of the olefin, and with the amount of phosphorus subsequently introduced. All of these factors are however very intimately inter-related.

These are the primary factors, but it will be expected that the visand other physical characteristics of the particular phenols employed have a corresponding effect upon the product, to some extent at least; this effect may, however not always, hold true where the degree of olefin absorption varies over comparatively'wide limits and where the percentage of phosphorus in the final compound also varies.

when cresylic acid, ortho-cresol and metacresol and the like are used in the manufacture of the anti-oxidant, we prefer to limit the olefin absorption to around one mol per mol of the phenolic material, i. e., to give a water insoluble product representing roughly 135 to 150 per cent by volume of the original phenol, in order ultimately to secure inhibitors that are sufliciently soluble in the higher gravity oils; the result of carrying the absorption of olefin farther is to make the anti-oxidant product less capable of absorbing the desired amount of phosphorus.

When the anti-oxidant starting material is prepared from phenol (Col-150K) .itself, e. g., 90 per cent phenol", the degree of absorption of olefin may be carried farther, for example to about two mols of olefin per mol of phenol (based on the assumption that the olefin is made up entirely of C4 hydrocarbons).

The preferred olefins are those containing from three to eight carbon atoms per molecule; the higher the molecular weight of the olefin, the more viscous the final phosphorus-containing product will be. Olefins containing more than eight carbon atoms per molecule tend to reduce the phosphorus content of the final inhibitor product. Ethylene (C2H4) on the other hand, is insufilciently reactive, requiring the use of fuming sulfuric acid and does not sufliciently reduce the acidity of the original phenol.

The best olefin starting materials are those containing from three to five carbon atoms per molecule, especially butylenes; fractions obtained from gases produced in the pyrolysis of hydrocarbon oils and rich in olefins of this approximate range represent advantageous and available raw materials.

After the reaction between the phenol and olefin has been carried to the desired degree of completion, the product is washed with water and dilute caustic soda in the manner set forth hereinabove and in the aforesaid co-pending applications. The resultant water-insoluble anti-oxidant material is then preferably dried. The drying may be accomplished by filtering this material through adsorbent clay or the like, the effect of which is to dehydrate and decolorize.

, Or, the drying may be accomplished by heating the anti-oxidant material to about 400 F. in suitable apparatus; this procedure dehydrates and tends to darken the anti-oxidant material.

The dry anti-oxidant may then be treated directly with phosphorus trichloride, or it may first be distilled to separate undesirable lowboiling and high-boiling constituents, respectively. Thus we may distill under a vacuum of from -11 in. to 28 in. Hg, to recover a fraction distilling over between 400 and 550 E, which fraction may then be treated with phosphorus trichloride. e lower boiling material, and

sometimes also the residue may be recycled for further reaction with olefins in the presence of sulfuric acid, .or used as an anti-oxidant.

The anti-oxidant material is then reacted with phosphorus trichloride as set forth in the aforesaid co-pending application of Cantrell and Turner, Serial No. 99,662, filed September 5, 1936.

The reaction is conducted by mixing phosphorus trichloride with the anti-oxidant material, in the desired amount and heating the mixture until the latter is substantially entirely free from chlorine or chlorides; insofar as the present invention is concerned, the dechlorination should be carried far enough to reduce the chlorine content to about 0.01 per cent or less. If this is not done, ammonium chloride or an analogous amine chloride may be formed in the final reaction stage in suflicient amount to contribute a definite haziness or cloudiness to oil to which the inhibitor is eventually added.

Before being brought into contact with the phosphorus trichloride the anti-oxidant material should bedried to remove any substantial amount of moisture contained therein. Conventional drying means may be employed. The dry antioxidant is then brought to a slightly elevated temperature, for example 80 F. andphosphorus trichloride is slowly added, the mixture being vigorously agitated by suitable mechanical means during the addition. Due to the fact that there is a copious evolution of dry HCl gas, it is advisable to add the phosphorus trichloride well below the surface of the liquid anti-oxidant in order to prevent the phosphorus trichloride from being swept out by the evolved gas and lost. After the desired amount of phosphorus trichloride has been added the temperature is slowly raised to around 350 to 450 F.; the mixture is then maintained at this temperature until there is no further evidence of hydrogenchloride evolution and the chlorine content of the product is 0.01 per cent or less. The dechlorination may be assisted by agitating the material and by passing an inert gas therethrough. The resultant intermediate product after cooling is ready for reaction with ammonia or whatever amine is employed.

As disclosed in the aforesaid co-pending application of Troy Lee Cantrell and James Otho Turner, Serial No. 99,662 filed September 5, 1936, the amount of phosphorus trichloride added is so regulated as to secure an intermediate product containing from one per cent, or less, to about five per cent of phosphorus; the amount of phosphorus trichloride added is preferably so limited as not to eifect completion of reaction with all of the anti-oxidant starting material. For most purposes, the intermediate products which give the best results are those containing from 1.7 to

4.0 per cent of phosphorus, depending somewhat upon the characters of the olefinic and phenolic raw materials from which the anti-oxidant starting material is prepared. Where the amount of phosphorus trichloride added is such as to stop short of completion of the reaction with all the anti-oxidant used, the resultant intermediate and final products will have suitable corrosion-inhibiting properties, while retaining much of the antioxidant value of the original starting material; even where the full amount of phosphorus trichloride is added, however, we have found that the final products prepared in accordance with our invention possess anti-oxidant and stabilizing properties to a substantial extent.

When ammonia is employed, it is preferably used in the form of anhydrous ammonia gas; as to the amines, any oil-soluble and preferably waterinsoluble amines may be employed, for example aniline, diphenyl amine, mixtures of alkyl or aryl amines or both, propyl amine, amyl amineand lauryl amine. Prima Ty, secondary and tertiary amines may be employed. The lower molecular weight amines are preferred but are limited by solubility of the final compound in oil tends to be reduced.

The amount of ammonia or phenol added will vary in accordance with the phosphorus content of the intermediate material treated. The best rule is to add enough ammonia or amine to provide an equimolecular proportion of nitrogen to phosphorus. For example, if a batchi of the phosphorus trichloride reaction product contains 31 pounds of phosphorus, enough anhydrous ammonia or amine should be added to supply 14 pounds of nitrogen. However, lower proportions of nitrogen to phosphorus, for example as low as 1:1, are sometimes desirable and the products comprise effective materials having special utilities. The final products in all cases contain ratios of phosphorus to nitrogen of approximately 2:1 or less.

It will be understood that in using anhydrous ammonia the actual amount of ammonia will be considerably in excess of the amount required to enter into combination with the intermediate material. In using anhydrous ammonia the general procedure is to saturate the phosphorus-trichloride-treated anti-oxidant at about atmospheric temperature with anhydrous ammonia and then blow the resultant mixture with inert gas to remove any excess of free ammonia. As inert gases, nitrogen, hydrogen, hydrocarbon gases and. the like may be employed.

The resultant products may then be used directly as inhibitors for addition to hydrocarbon oils in amounts which will ordinarily range from about 0.25 to 2 per cent by weight of the 011. Before adding the inhibitor to the oil, it may first be decolorized by conventional means, as for example by filtration through adsorbent clay or the like.

Alternatively, the original anti-oxidant starting material or the phosphorus trichloride reaction product may be similarly decoloi'ized, where a light-colored final product is desired.

The following examples will serve to illustrate our invention in some of its more specific embodiments.

EXAMPLE 1 (a) Preparation of anti-oxidant starting material 20 gal. of per cent phenol were mixed with 5 per cent by weight of 94.5 per cent sulfuric acid (C. P.). Olefin gas, composed primarily of C4 hydrocarbons, was then introduced into close contact with the phenol-acid mixture until the volume of the reacting mixture increased to about 45 gal. This product was washed with 10 gal. of 10 per cent caustic soda and later with 10 gal. of water. After washing the recovered product amounted to about 40 gal. The product was then distilled under a vacuum of 11 to 12 inches of mercury. The distillate was cut into three fractions. That portion distilling over at vapor temperatures between 300 following properties:

Gravity: A. P. I 16.8 Viscosity, S. U. V.: F., sec 185 Color, Saybolt 13 (b) Preparation of intermediate material 82.5 parts by weight of the above distillate were treated with 17.5 parts by weight of phosphorus and 550 F. had the trichloride and thoroughly dechlorinated at 400 F., yielding an intermediate material having the following properties:

Gravity: A.P I 12.5 Viscosity, S. U. V.: 210 F., sec 113.7 Color, N. P, A 3 Phosphorus, per cent by weight 3.37 Chlorine, per cent by weight 0.01

( Preparation of final inhibitor Gravity: A. P. I 12.7

Viscosity, S. U. V.: 210 F., sec 118.

Color, N, P. A 3.

Phosphorus, per cent by weight 3.21

EXAMPLE 2 83 parts by weight of the intermediate material referred to in Example 1 (b) above were treated with 17 parts by weght of diphenyl amine (technical grade). The mixture was agitated at 200 F. for one hour and then cooled. The resulting material had the following properties:

Gravity: A. P. I 11.9 Viscosity, S. U. V.: 210 F., sec Color, N. P. A Dark Phosphorus, per cent by weight; 2.64

The inhibitors prepared in accordance with our invention and as exemplified by those given in the foregoing examples are all excellent inhibitors for addition to hydrocarbon lubricating oils and when added thereto in amounts up to 2 per cent, for example from-0.25 to 1.0 per cent of the oil, result in improved and advantageous lubricating compositions. These inhibitors all are permanently soluble in hydrocarbon oils, even in oils high in paraflinicity, and they strongly inhibit corrosion of metal bearing alloys such as those of silver, cadmium, and copper, under conditions where highly paraflinic oil alone would cause such corrosion. On the other hand, these inhibitors are stable at atmospheric and moderately elevated temperatures and do not tend to settle out nor form sludge, nor to deposit on nor attack metal surfaces such as those of tin plate, teme plate, and the like when packaged and stored prior to sale and use. Their stability is such that they do not become active until the oil compositions containing them are raised to temperatures of around 200 F., or at any rate to temperatures considerably above the temperatures at which inhibitors prepared by reacting phosphorus trichloride and anti-oxidant become active; by reason of this fact, these improved inliibitors are more effective at the actual points of application where required and do not diminish in efiiciency through action at lower temperatures.

Not only do these inhibitors have excellent antitheir chemical nature is such that should any hydrolysis occur, the organic products of such hydrolysis are in themselves anti-oxidant and non-corrosive materials.

The following tables will serve to illustrate the eifectiveness of our improved inhibitors and the value of lubricating compositions containing The lubricating oil referred to in the tests them: listed in the tables given herein was an S. A. E. Table I 10 oil which had been previously treated with aluminum chloride. 5 Untreated ile fi l i lg i t r The Special oxidation and corrosion test regggfigq ff ferred to in the foregoing tables is conducted as follows: An alloy bearing shell of certain com- Ma e-1 1; p r y Weishfl monly used standard dimensions is submerged in fi f jjj 300 cc. of the oil or oil composition in a 400 c0. 10 G n 32 2 Pyrex beaker and heated in a thermostatically 018044 controlled oil bath to 175 C. (347 F.), and air, 7-198 at the rate of 2000 cc. per hour, is bubbled 1 through the oil in contact with the bearing shell. 3} At the end of 48 to 96 hours, the loss of weight 0806 and the condition of the bearing shell are deigg. termined, the bearing shell being washed free of oil and dried before weighing. When determining the effectiveness of various'improvement 1 agents the usual procedure is to run a "blank" test simultaneously with the oil composition be- Level-1108a ldmiiaufi 600 6%?) ing tested, employing for that purpose a sample of the untreated oil. I P$F l i% i? I i2 3% In this test it is advantageous to employ com- 9 1300 mercial bearing shells. These shells comprise a 25 Initial -1; s3 88 suitable metal backing faced with the alloy bear- F1181 ing metal. In this way, the actual bearing face Time oxidize 4s 48 is subjected to severe deteriorative conditions.

3%; 333 By comparison of the results of such tests with Quantity 0} 011: cc 300 .300 actual service tests, we have found them to be in 30 R 3L2 3L 6 substantial agreement as to the suitability of par- Viscosity, s U.V.: ticular lubricants.

3" 23 In the tests given in Tables I and II, we em- 050 0. 47 ployed so-called silver-cadmium bearings of 33 the following approximate composition:

35 as. 2480 a0. 5515 36. 0970 36. 5609 Metal Percent -0. 1510 +0. 0004 Appearanea"; Etched Good Cadmium 98 Tabl 11 Silver. 1 40 Coppen. 1 U 011 containing lif 'ig rt 2 1 In these tests the loss in weight, while not ex- ExamPlB 2) tremely high when expressed as per cent loss, Makmp. Pemntby weight. is nevertheless very significant, as the bearing 45 Lubricating oil 100 09.0 shells used have an alloy facing of only 0.008 to gggfg fig 0.012 in. thickness on a highly resistant back- Gravity: A RI 0 32.5 32.4 ing and the observed losses in the reported tests igff gf'ggl gffl ffj; 2;,32 1 i33 often represent a loss of the order of ten per cent VisoosigyFS.U.V-: of the alloy facing. 5 2%; 2213 Various modifications in the operating pro- 10 0 cedures mentioned hereinabove will. suggest 2 8 3- themselves to those skilled in the art. For ex- F 46g 1g ample, we have described washing the phenolr, 1.5 L5 olefin reaction product with water and dilute 55 i f g t g-gg caustic soda solution to effect neutralization and $figfigjj "5135 removal of the acid or acids (e. g. sulfuric acid fig f d. 1b m m and sulfonic acids) remaining in the reaction g 'iifi'fi 600 600 mixture after the introduction of the olefins i3 $3 has been discontinued. Such neutralization and 60 5000 8000 removal may be effected in other ways, as by extraction with aqueous alcohol, contact with as 90 100 120 solid alkalis such as calcium or sodium carbonate, idfltmn 48 48 or by contacting the reaction mixture with solid hr 2%; 2 3 7 adsorbents such as fullers earth, activated car- 65 2F hon, or the like 8it$t cc 300 Whe ever the expression highly paraflinic oil is employed herein and in the claims hereinafter 100 I3-.'.--' 210 20s made,'it is in general intended to indicate invisozosigifia 3; 3- bricating oils conforming in physical properties 70 Carbon esidue: 0. a0 0. 3a to 0118 prepared from Pennsylvania crudes; these gigagfig g gfiff ff 3? 8 3 highly paraffinic oils are either oils derived Cadmium-Silver bearing: from Pennsylvania crudes, or oils which have Night 2%? G ggg been refined or blended to approach or even ex- +0I0095 ceed the latter oils in paraflinicity. Where var- 75 ious materials are referred to as being soluble in 2,157,479 'such parafiinic oils, this expression is intended to mean that such materials may be incorporated into such oils in amounts up to ten per cent,

without producing any haziness nor cloudiness in the appearance of the resultant compositions, at least under atmospheric temperature and under the ordinary conditions to which such oil compositions are subjected in storage and handling prior to their actual use as lubricants.

While we have described our invention herein above with reference to various preferred forms and embodiments, and with reference to various specific examples, it will be understood that our invention is not limited to the details of such illustrative embodiments or examples but may be variously practiced and embodied within the scope of the claims hereinafter made. Moreover, while we have in certain instances specifically given certain preferred ranges and proportions, it will be understood that our invention is not limited thereto, and that such preferred ranges and proportions are in general selected for particular products and particular purposes; variations in proportions and in the methods of preparation result in products of different characteristics, such products having individual advantages and utilities.

What we claim is:

1. A method of preparing an oil-soluble phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises reacting an olefin and a phenol in the presence'of a catalyst, removing alkali-soluble material, treating at least a portion of the resultant product with phosphorus trichloride, and treating the product thereby obtained with a reagent selected from the class consisting of anhydrous ammonia and oilsoluble amines. I

2. A method of preparing an oil-soluble phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises reacting an olefin and a phenol in the presence of a catalyst, removing. alkali-soluble material, treating at least a portion of the reaction product with phosphorus trichloride to obtain a resultant product containing from one to five per cent by weight of phosphorus, and treating said resultant product with a reagent selected from the class consisting of anhydrous ammonia and oil-soluble amines.

3. A method of preparing an oil-soluble phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises re-- acting an olefin and a phenol in the presence of a catalyst, removing alkali-soluble material, treating at least a portion of the reaction product with phosphorus trichloride to obtain a resultant product containing from one to five per cent by weight of phosphorus, and treating said resultant product with a reagent selected from the class consisting of anhydrous ammonia and oil-soluble amines in such amount as to give a final product having a ratio of nitrogen to phosphorus lying between 1:1 and 1:2.

4. A method of preparing an oil-soluble organic phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises reacting an olefin and a phenol in, the presence of sulfuric acid, neutralizing the resultant anti-oxidant product, distilling the neutralized product to recover a fraction of intermediate boiling range, reacting said fraction with phosphorus trichloride, and treating the lastnamed resultant phosphorus-containing product with a reagent consisting of the class of anhydrous ammonia and oil-soluble amines.

5. A method of preparing an oil-soluble phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises reacting an olefin and a phenol in the presence of a catalyst, treating at least a portion of the alkaliinsoluble reaction product with phosphorus trichloride, and treating the phosphorus-containing product thereby obtained with anhydrous ammonia.

6. A method of preparing an oil-soluble phosphorus compound suitable as an improvement agent for hydrocarbon oils, which comprises reacting an olefin and a phenol in the presence of a catalyst, treating at least a portion of the alkaliinsoluble reaction product with phosphorus trichloride, and treating the phosphorus-containing product thereby obtained with an oil-soluble and water-insoluble amine.

7. An improvement agent for hydrocarbon lubricating oils, comprising an ammonium or aminosalt of a phosphite ester of a water-insoluble alkali-insoluble secondary or tertiary alkylated phenol.

8. A lubricant comprising a hydrocarbon oil and a small quantity of an ammonium or aminosalt of a phosphite-ester of a water-insoluble secondary or tertiary alkylated phenol.

TROY LEE CANTRELL. JOE. GORDON PETERS.

CERTIFICATE OF CORRECTION.

TROY LEE CANTRELIJ" ET AL.

It is hereby certified that erroreppears in the printed specification of the above numbered patent requiring column, line 51;, for-the numeral .0901 2" correction as follows: Page 5 second read 0.90h2; page 7, second column line M claim7, after "water-insoluble" insert and; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 6th day of June, A. D; 1959.

(Seal) l-l'enry' Van Arsdale Acting commissioner of Patents. 

